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. (No Model.) 2 sheets-sheet 1.

W. S. SHARPNBCK. PEDAL MBGHANISM No. 580,512. Patented Apr. 13, 1897.

2 Sheets- Sheet 2.

(No Model.)

W. S. SHARPNECK.

PEDAL MBOH-ANISM..

N0. 580,512. PatentedApr. 13, 1897.

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VILLIAM S. SHARPNEOK, OFOHIOAGO, ILLINOIS, ASSIGNOR OF FIVE-SIXTHS TO OYRENIUS A. DAVID, OF SAME PLACE, AND ALEXANDER C. OALVERT,

OF OAMBRID GE, ENGLAND.

PEDAL MECHANISIVI.

SPECIFICATION formingpart of Letters Patent No. 580,512, dated April 13, 1897'.

Application filed July 20, 1896. Serial No. 599,793. (No model.)

To LZZ whom, it may concern.

Be it known that I, WILLIAM S. SHARPNECK, of Chicago, in the State of Illinois, have invented certain new and useful Improvements in Pedal Mechanism, of which the following is a specification.

My invention relates to pedal mechanism for applying power in propelling bicycles; and the object of my improvement is to provide I o suitable means for connecting the pedal mechanism with the spindle of the wheel in conjunction with ball-bearings for the spindle in the frame. I attain this object by the means illustrated in the accompanying drawings, in which-- Figure 1 is a side elevation of a bicycle provided with my invention. Fig. 2 is a detail representing a fragment of a plan view, part-ly in section, taken on the line 2 2 of Fig. l.

zo Fig. 3 is a detail representing a fragment of a rear elevation taken on the line 8 3 of Fig.

l. Fig. 4 is a fragment of a horizontal section taken partly on the line of the axis of the spindle of the drive-wheel and partly on 25 a higher line, so as to show one of the pedallevers in plan view and the other and its connection with the spindle in sectional View. Fig. 5 is a detail showing an enlarged sectional view on the line 5 5 of Fig. 4. Fig. 6

3o is a detail showing in fragment a face View of the rack.

In the drawings, A designates the drivewheel; B, the frame; O, the pedal-levers; D, the rack, and E the pinion. The spindle a 3 5 of the drive-wheel is journaled in the frame at d', Fig. 4, and provided with ball-bearings. A sleeve having a polygonal part a2 for applying a wrench is threaded upon the spindle and has its inner extension made 4o conical to form a counterpart of the ballbearing. It has a reduced cylindrical extension in the outer direction as, which forms the bearing for the pinion and is made of hardened steel. The bore of the pinion is provided with eccentric pockets e, in which are placed hardened rollers e. The rollers come between the reduced cylindrical extension and the eccentric bottom of the pockets and are pressed by elliptic springs e2 toward 5o the shallow part of the pockets, so as to bind and form a clutch which fixes the pinion to the sleeve for rotation in the forward direction, but leaves it free to revolve upon the sleeve in the backward direction. The pinions are made of hardened steel and have rings e3, of softer metal, shrunk upon their ends and preferably projecting beyond the outer line of the cogs to form guides for the rack, the purpose being to aid in preventing any lateral movement of the pedal-levers. 6o The eXtreme extension of the spindle is reduced and threaded in the opposite direction from the other part, so that a jam-nut E, applied thereto, can be made to secure the sleeve, keep the pinion in its place thereon, and close the outer ends of the roller-pockets, the other ends being closed by the shoulder at the juncture of the polygonal part with the reduced cylindrical part of the sleeve.

The pedal-levers are pivotally mounted on 7o the frame at opposite sides in advance of the drive-wheel by means of pins c, attached to the horizontal bar and provided with ballbearings c, the pins being preferably supported at their outer ends by means of bracepieces O, connecting them with the upper part of the frame to avoid torsion.

The part of the levers behind the pivotal mounting forms a yoke C2, to which the ends of the rackare connected, and the lower mem- 8o bers of the yoke striking the pinions operate as stops to the down movement of the fore part of the levers. A walking-beam F is pivotally mounted on a bar F of the frame and has one end connected with each of the pedal- 8 5 levers, at a point in front of their connection with the frame, by a iieXible cable or, preferably, telescoping rod G, whereby the power applied to one of the pedal-levers to force it down will cause the opposite one to be correspondingly raised.

The front end of the levers is curved upward in order to elevate the eXtreme end, so that the pedals H can be centrally mounted on the levers and brought nearer together 95 than pedals mounted on cranks. The pedals have ball-bearing connection with the pedallevers.

The front part of the levers is made in sections, the end of each section being provided IOO yIo

with an eye c2 and set-screw, whereby the leverage can be shortened or lengthened for increasing or slackening the speed'.

The mechanism is designed to drive the wheel forward only and in this use the rods G are subject to a pulling strain only, but an attempt to run the'wheel backward would puit a thrust upon said rods liable to bend them if rigid. Therefore they should be made to telescope, or a cable or chain should be used in order to avoid liability to breakage in case of misuse or accidental running of the wheel backward; and to further protect the wheel in this regard provision is made at the top of thel racks by providing sufiicient space between the upper members of the yokes and the toothed part of the racks to permit the pinions to run off thetoothed parts and thus be thrown out of-gear in case of prolonged running of the wheel backward. rlhe rack and' pinion cannot be thrown out of gear in theiregular operation because thestop ofthe lower member ofthe yoke with the pinion on one side of the wheel, through the connections of thez rods G, is timed to check the motion of the yoke on the other side before the pinion runs 0E' the rack at its upper end.

Having thusl fully described my invention, what Iclaim is- 1. rlhe combination with a ball-bearing in a wheel-frame of the wheel-,spindle provided with sleeves threaded thereon at opposite sides i in unison, and a pair of racks connected with the pedal-levers and adapted to engage the pinions as specified.

2. In a pedal mechanism for bicycles the combination with the driving-spindle of a sleeve threaded thereon and having a polygonal part with aconical extension on one side and a reduced cylindrical extension on the otherv side, a pin-ion having its borel fitted on the reduced cylindrical extension, a clutch adapted to fix the pinion to the sleevefin the forward rotation and to free it therefrom in the backward rotation and means for securing the pinion from displacement on the sleeve as specified.

WILLIAM S. SHARPNECK.

Witnesses:

ANNIE M. ADAMs, HARRY WAsHBURN. 

